Pesticide Residues in Aquatic Invertebrates - Pesticides: Evaluation of Environmental Pollution - page 325

Filopaludina martensi , by disrupting the endocrine system. Single-cell gel electrophoresis
(SCGE) assay showed that DDT and its derivatives are genotoxins, causing damage to
DNA in Dreissena polymorpha (Binelli et al. 2008). Freshwater mussels such as unionid
mussels, Elliptio complanata , have been used as sentinel animals to detect OCP residues in
freshwater ecosystems in North America (Renaud et al. 2004; Won et al. 2005) and used
as a bioindicator in Lake Maggiore, Italy (Riva et al. 2010). Reports have shown that OCPs
have been detected in mollusks in several countries including Southeast Asia. Siriwong
(2006) and Siriwong et al. (2008) reported that low concentrations of banned OCPs, such
as HCH, heptachlor and heptachlor epoxide, DDT and its derivatives, and endosulfan
(α-, β-, and -sulfate) are still present in apple snail Pomacea sp. Furthermore, in Canada,
the Rideau River near Ottawa was used to detect OCPs in D. polymorpha and E. compla-
nata (Renaud et al. 2004) and also OCPs presented in D. polymorpha in Maggiore Lake,
Italy (Binelli et al. 2004; Binelli et al. 2007).
11.2.2.2 Effect of Organophosphate on Mollusks
OPPs such as malathion, thiometon, and disulfoton were used to control insects and
protect crops. In 1986, the Rhine River was accidently contaminated with several tons of
pesticides, mainly thiometon and disulfoton. After three and a half months, high con-
centrations of pesticides were detected in sediment and the Zebra mussel D. polymorpha
(a freshwater bivalve), which is an important part of the diving duck's diet. Significant
mortality was seen in those ducks that had fed on the mussels (Dauberschmidt 1995).
In vitro, it was found that 88% and 93% of D. polymorpha died when they were admin-
istered 50 mg/L of thiometon and 30 mg/L of disulfoton, respectively (Dauberschmidt
et al. 1996). Additionally, Dauberschmidt et al. (1997) reported that organophosphates,
including 10 mg/L of disulfoton and 6 mg/L of thiometon, can create subacute expo-
sures (10 day) on D. polymorpha . Chlorpyrifos, a broad-spectrum organophosphate
insecticide, has been shown to reduce cholinesterase activity in the Asian clam,
Corbicula fluminea, , and reduced their capacity to burrow into the substrate (Cooper and
Bidwell 2006).
11.2.2.3 Effect of Carbamate on Mollusks
Carbamate pesticides such as carbaryl (1-naphthyl methyl carbamate) have been used
for pest control in crops and domestic animals. CMs are not persistent in the ecosystem.
However, CM residues have been detected in surface water. The toxicity of CMs is similar
to OPs. However, there is some documentation reporting that CMs are higher in toxicity
and exhibit a greater sensitivity to the inhibition of AChE activity than OPs. In vivo, the
gastropod Biomphalaria glabrata was exposed to 1 mg/L of carbaryl, which significantly
inhibited enzyme activity (Kristoff et al. 2010).
11.2.2.4 Effect of Pyrethroid on Mollusks
Synthetic pyrethroids were used for agricultural and public health purposes after OCPs
were banned. Pyrethroids are very toxic to insects and crustaceans, but are less toxic to
mammals (Coats et al. 1989). However, both acute and lethal effects on nontarget inver-
tebrates are of interest. A study in India administered cypermethrin and alphamethrin
in the freshwater snail Lymnaea acuminata. This resulted in a significant increase in the